1. Field of the Invention
The present invention relates to antennas for transmission and reception of radio frequency communications. More particularly to an antenna employing planar shaped radiator elements which are especially well adapted for cellular telephone communications and which are employable individually or engageable to other similarly configured radiator elements, for both increased gain and steerability.
2. Background of the Invention
Since the inception of cellular telephones, cellular service providers have had the task of installing a plurality of antenna sites over a geographic area to establish cells for communication with cellular telephones located in the cell. From inception to the current mode of cellular broadcasting and reception, providers have each installed their own plurality of large external cellular antennas for such cell sites. Generally, such antennas or cable hookup is necessary to provide a television receiver with the required signal strength to provide a perfect picture and sound to the viewer.
In practice, cell sites are grouped in areas of high population density with the most potential users. Because each cellular service provider has their own system, each such provider will normally have their own antenna sites spaced about a geographic area to form the cells in their respective system. In suburban areas, the large dipole or mast type antennas must be placed within each cell. Such masts are commonly spaced 1-2 miles apart in suburban areas and in dense urban areas masts may be as close as ¼-½-mile apart.
Such antenna sites with large towers and large masts are generally considered eyesores by the public. Because each provider has their own system of cell sites and because each geographic area has a plurality of providers, antenna blight is a common problem in many urban and suburban areas.
The many different service providers employ many different technologies such as 3G, 4G, GSM or CDMA. They also employ these technologies on bandwidths they either own or lease and which are adapted to the technologies. Consequently, the different carriers tend to operate on different frequencies and, because conventional dipole and other cell antennas are large by conventional construction, even where the different providers are positioning sites near each other, they still have their own cell towers adapted to the length and configuration of the antennas they employ for their systems and which are adapted to their individual frequencies.
As many carriers and technologies employ different sized, large antennas, even if they wanted to share cell sites and antennas more often, the nature of the antennas used conventionally discourage it. The result being a plethora of antenna sites, some right next to each other, with large ungainly and unsightly antennas on large towers.
External antennas generally take the form of large cumbersome conic or Yagi type construction and are placed outdoors either on a pole on the roof top of the building housing the receiver or in an attic or the like of a building. These antennas are somewhat fragile as they are formed by the combination of a plurality of parts including reflectors and receiving elements formed of light weight aluminum tubing or the like having various lengths to satisfy the frequency requirements of the received signals and plastic insulators. The receiving elements are held in relative position by means of the insulators and the reflectors elements are grounded together.
Assemblage of these antennas is required either by the user or by an installer. This creates the possibility of some of the elements bending or breaking during construction which must then be replaced, increasing the already high economic cost of the antenna. Alternatively, the user or installer may become injured by falling, further increasing costs.
Externally placed antennas of this type are continually subjected to the elements. Even if not damaged or destroyed by the elements during harsh weather conditions, over time these antennas will generally produce poor reception or reduced reception during extreme weather conditions or will gradually reduce their ability to produce acceptable reception over time due to mechanical decay. In addition to the above deficiencies, this type of receiving antenna is aesthetically unappealing.
Other antennas that are currently used are indoor antennas which are easy on the eyes but unacceptable for producing a good picture and sound. The most common and effective of these indoor antennas is the well known dual dipole type positioned adjacent to or on the television receiver and affectionately referred to as “rabbit ears.” These antennas are generally ineffective for fringe area reception and are only effective for strong local signal reception. When low frequency signal reception is desired, the dipoles must be extended to their maximum length, making the “rabbit ear” antenna susceptible to tipping over or interfering with or causing possible damage to any adjacent objects.
Cable systems are also currently used for delivering signals to television receivers. This system is highly successful for delivering picture perfect signals to a television receiver over a large range of frequencies. One of the strongest disadvantages to the cable signal delivery systems is the economic cost of installation and the periodic cost of the signal delivery to the user which can run as high as one hundred dollars monthly.
Satellite dishes, with their accompanying accessories, are another of the present methods of receiving television signals. This method is popular and successful for receiving signals from fixed in position satellites. Systems of this type require large diameter dishes, generally in excess of six feet and ideally about twelve feet, for receiving acceptable signal levels. Small dishes under two feet in diameter are presently unusable for all but the most powerful satellite transmitters. The acceptable sized dishes are ugly to view and because of size are hard to hide from sight. In addition, the systems as they exist today are quite expensive and therefore not available to all who desire to view picture perfect television reception.
There has not been a highly signal sensitive visually attractive indoor television antenna until the emergence of the instant antenna.
The radiator elements are capable of concurrent communications between users and adjacent antenna nodes having the same radiator elements in one or a wide variety of bandwidths. The unique configuration of the individual antenna radiator elements provides excellent transmission and reception performance in a wide band of frequencies between 470 MHz to 5.8 GHz. Such performance in such a wide bandwidth has heretofore not been achieved and the single radiator element disclosed is capable of employment for reception and transmission in widely used civilian and military frequencies such as 700 MHz, 900 MHz, 2.4 GHz, 3.5 GHz, 3.65 GHz, 4.9 GHz, 5.1 GHz and 5.8 GHz. The radiator element actually has reasonable performance capabilities up to 1.2 gbps, rendering it capable of deployment for antenna towers for concurrent reception and transmission of RF frequencies between 470 MHz to 5.8 GHz which is heretofore not achievable in a single antenna element. Such deployment will minimize the number of towers and antennas needed in a grid or communications web, yet provide for the maximum number of different types of communications from cellular phones to HDTV.
2. Prior Art
Conventionally, cellular, radio, and television antennas are formed in a structure that may be adjustable for frequency and gain by changing the formed structure elements. Shorter elements for higher frequencies, longer elements for lower, and pluralities of similarly configured shorter and longer elements to increase gain or steer the beam. However, the formed antenna structure or node itself is generally fixed in position but for elements which may be adjusted for length or angle to better transmit and receive on narrow band frequencies of choice in a location of choice to serve certain users of choice. Because many communications firms employ many different frequencies, many different such individual antenna towers are required with one or a plurality of such towers having radiator elements upon them to match the individual frequencies employed by the provider for different services such as WiFi or cellular phones or police radios. This can result in multiple antenna towers, within yards of each other, on a hill, or other high points servicing surrounding areas. Such duplication of effort is not only expensive but tends to be an eyesore in the community.
As such, when constructing a communications array such as a cellular antenna grid or a wireless communications web, the builder is faced with the dilemma of obtaining antennas that are customized by providers for the narrow frequency to be serviced. Most such antennas are custom made using radiator elements to match the narrow band of frequencies to be employed at the site which can vary widely depending on the network and venue. Also, a horizontal, vertical, or circular polarization scheme may be desired to either increase bandwidth or connections. Further consideration must be given to the gain at the chosen frequency and thereafter the numbers elements included in the final structure to meet the gain requirements and possible beam steering requirements.
However, such antennas, once manufactured to specific individual frequencies or narrow frequency bands, offer little means of adjustment of their ultimate frequency range and their gain since they are generally fixed in nature. Further, since they are custom manufactured to the frequency band, gain, polarization, beam width, and other requirements, should technology change or new frequencies become available, it can be a problem since new antennas are required to match the changes.
Still further, for a communications system provider, working on many different bands with many frequencies in differing wireless cellular or grid communications schemes, a great deal of inventory of the various antennas for the plurality of frequencies employed at the desired gains and polarization schemes must be maintained. Without stocking a large inventory of antennas, delays in installation can occur.
Such an inventory requirement increases costs tremendously as well as deployment lead time if the needed antenna configuration is not at hand. Further, during installation, it is hard to predict the final antenna construction configuration since in a given topography what works on paper may not work in the field. Additionally, what exact gain and polarization or frequency range which might be required for a given system when it is being installed might not match predictions. The result being that a delay will inherently occur where custom antennas must be manufactured for the user if they are not stocked.
This is especially true in cases where a wireless grid or web is being installed for wireless communications. The frequencies can vary widely depending on the type of wireless communications being implemented in the grid, such as cellular or WiFi or digital communications for emergency services. The system requirements for gain and individual employed frequencies can also vary depending on the FCC and client's needs.
Still further, the infrastructure required for conventional cellular, radio and other antennas, requires that each antenna be hard-wired to the local communications grid. This not only severely limits the location of individual antenna nodes in such a grid, it substantially increases the costs since each antenna services a finite number of users and it must be hardwired to a local network on the ground.
As such, there is a continuing unmet need for an improved antenna radiator element, and a method of antenna tower or node construction, allowing for easy formation and configuration of a radio antenna for two way communications such as cellular or radio for police or emergency services. Such a device would be best if modular in nature and employ individual radiator elements which provide a very high potential for the as-needed configuration for frequency, polarization, gain, direction, steering and other factors desired, in an antenna grid servicing multiple but varying numbers of users over a day's time.
Such a device should employ a wideband radiator element allowing for a standardized number of base components adapted for engagement to mounting towers and the like. The components, so assembled, should provide electrical pathways electrically communicated in a standardized connection to transceivers. Such a device should employ a single radiator element capable of providing for a wide range of different frequencies to be transmitted and received. Such a device, by using a plurality of individual radiator elements of substantially identical construction, should be switchable in order to increase or decease gain and steer the individual communications beams.
Employing a plurality of individual wideband radiator elements, such a device should enable the capability of forming antenna sites using a kit of individual radiator element components, each of which are easily engageable with the base components. These individual radiator element components should have electrical pathways which easily engage those of the base components of the formed antenna to allow for snap-together or other easy engagement to the base components hosting the radiator elements. Such a device should be capable of concurrently achieving a switchable electrical connection from each of the individual radiator elements across the base components and to the transceiver in communication with one or a plurality of the radiator elements.